ISSN - ISRM

Dynamic Properties of Sandstone Rock Subjected to Cyclic Loading73.0 TESTED ROCKThe rock tested was mostly carboniferous sandstoneobtained from the rock burst prone Darkov coal mine.The rock cores represent borehole Darkov 265-01. Thesamples were obtained from borehole cores in the saddlelayer sandstone, at an approximate depth ranging from930 to 980 m below surface in the case of Darkov.Samples were obtained from Darkov mine and sampleNo. 95-113 is referred to as Darkov 265-01-1 (thenreferred to as D1), from sample No. 114-118 as Darkov265-01-2 (D2) etc., and hereafter, they are referred to asD1, D2, D3, D4, D5, D6, D7, D8 and D9, respectively.Details about various nomenclatures used to identifyrock samples and their respective depth is provided inTable 1. The term “sample” refers to the block or cores ofrock obtained from a site, while the term “rock specimen”refers to the specific piece of rock prepared and tested.Fig. 2 shows the prepared rock specimens from differentsamples obtained from borehole Darkov 265-01.The tested rock specimens were of L/D ratio of 1 with anaverage diameter of 47.7 mm. Rock samples obtainedfrom vertical borehole in the form of cores and rockspecimens were prepared from the obtained cores andthus, loading direction in uniaxial compression testing inthe laboratory was parallel to borehole axis. Rockspecimens were prepared and tested according to ISRMtesting procedure and guidelines (Fairhurst and Hudson,1999).Table 1 : Nomenclature used to identify rock samples with their respective depth andnumbers of tested rock specimensSample Identification Symbol Depth below surface (m) SpecimensBorehole: Darkov 265-01, Mine: Darkov95-113 Darkov 265-01-1 D1 929-947 2114-118 Darkov 265-01-2 D2 948-952 2119-122 Darkov 265-01-3 D3 953-956 4123-126 Darkov 265-01-4 D4 957-960 4127-129 Darkov 265-01-5 D5 961-963 5130-134 Darkov 265-01-6 D6 964-968 5135-138 Darkov 265-01-7 D7 969-972 5139-147 Darkov 265-01-8 D8 973-981 5148-149 Darkov 265-01-9 D9 982-983 5Fig. 2 : Prepared rock specimens showing sample disturbance from borehole Darkov 265-01Volume 1 v No. 1 v January 2012